Source: 9 to 5 Mac
quote: It’s no coincidence that Apple’s support site doesn’t have downloads for the new Aperture, iWork, and iLife updates. They aren’t in our Software Update system either – and there’s a good reason for that. With Mavericks, we have changed the way we distribute updates for legacy versions of our appsRather than maintain separate updates for these in addition to the Mac App Store versions of each app, Apple has decided to eliminate their legacy software update system for apps entirely. Instead, when Mavericks discovers legacy apps installed on your Mac, it provisions them as a Mac App Store purchase using your Apple ID. It saves us a lot of time, effort, and bandwidth. After the provision is complete, it will appear in your Mac App Store history as though you have purchased the Mac App Store version of the app.While we are aware that this enables piracy of our apps for unethical users, Apple has never taken a strong stance or action against piracy in the past. We like to believe that our users are honest, even if that belief is in vain.